Apparatus for applying retro-reflective bands on cylindrical surfaces



Jan. 28, 1969 M. 1 JOHNSON ETAL 3,424,127

APPARATUS FOR APPLYING RETRO-REFLECTIVE BANDS ON CYLINDRICAI.: SURFACES Filed Dec. 11, 1967 Sheet of 2 A y /c/Gw/ gan ,43% Mm@ Jan. 28, 1969 M. l.. JOHNSON ETAL 3,424,127

APPARATUS FOR APPLYING RETRO-REFLECTIVE vBANDS ON CYLINDRICAL SURFACES Filed Deo. ll, 1967 Sheet g of 2 INVENTORS /I/fz V//VLJaH/vsa/v Q/vaw f? E Vqsffak United States Patent O 7 Claims ABSTRACT OF THE DISCLOSURE An apparatus for applying a reflex-reflecting stripe around the circumference of a cylindrical member by first coating the member with an adhesive material and then applying a layer of reflex-reflecting particles to the adhesive band. The apparatus has a first coating wheel for the direct application of an adhesive material and a horizontally spaced applicating wheel for applying a layer of reflexereflective particles to the adhesive band.

The present invention relates to an apparatus for placing a reflex-reflecting stripe on conveyor-transported objects, and in one respect relates to a machine for applying a stripe around a cylindrical object such as a can before the saine is filled such that the same may be sorted after passing through the processing steps in a Cannery.

It has been found to be necessary to apply markings to cans in the canning industry to afford a means for sorting cans after they have been filled and sealed but before identifying labels are applied thereto. The sorting is necessary to separate two or more different grades of foodstuffs orto sort different foodstuffs which are canned and cooked or processed simultaneously. This sorting operation is generally done after the cans leave the continuous cookers in the canning plant; and it is therefore necessary to apply onto the cans filled with similar content some identifying detec-table mark prior to the cans being lled and sealed, which mark will remain on the cans and afford a sure method of sorting the marked cans from the others when the products leave the cooker and before the identifying labels are applied.

Previous to the present invention, the identifying marks on the cans have often been a black ink band which completely encircles the can body. The can bodies containing different products are marked with bands having different axial locations along the cylindrical can body. These ink bands may be placed upon the can by a stencil or irnprinted on the can body by a printing roll which carries ink to and transfers the same to the surface of the can body. These black rings or ink bands are then used for sorting in different sorting machines where the presence of the circumferential band at a predetermined height or location along the cylindrical can body or the absence of the band is the means by which the different products or grades of products can be segregated. With these ink bands, photocells are positioned to respond to variations in intensity of light reflected from each can body passing in a single file, and the cans are sorted because the photocell either fails to receive any reflected light because of the presence of the black band or it sorts the can because of the absence of the black band and the reception of reflected light in the photocell.

The difficulty with this type yof coding system is that during the handling of the cans to carry out the usual operations of filling, sealing, cooking, and conveying the ink band becomes marred causing removal of part of the ink from the can, which at the marred area permits the light from the lighting source to reflect therefrom to the photocell, thus mistakenly reading the code on a can such Fice that there is a likelihood that a can of peach halves could be labeled as diced peaches. Also, where there is no mark on the can and reflected light should be received, the can may possibly be dented such that the surface presented to the light does not present the anticipated reflection. The can then passes as one with a dark band.

A method of applying a mark, which method is disclosed and claimed in the co-pending application of Melvin L. Johnson, Ser. No. 689,709, filed Dec. l1, 1967, and assigned to the same assignee as this application, provides a reflex-reflective marking system which fulfills the need. The reflex-reflective or retro-reflective mark permits the sorting equipment to operate over a greater area of each can as they move through the sorting equipment. Prior known apparatus, however, has had many shortcomings in applying the marks. The shortcomings or difiiculties encountered with the prior-known apparatus were: a buildup of adhesive on the adhesive coating roller when conventional ink-type printing machines were used (this was particularly difficult when the coating machine had to be stepped because of a jam developing somewhere in the canning operation); a lack of circulation of the adhesive composition causing it to dry more quickly in the supply reservoir; a marginal retro-reflective particle supply reservoir; such apparatus required additional can handling since the cans had to be elevate-d to the vertically disposed coating machines or elevated back to the line after passing through the coating machines; and the prior machines did not permit much variation in the axial location of the marks on the can bodies.

The present invention affords an apparatus which overcomes these difliculties.

The present invention provides a novel machine readily adapted to be inserted into the can-handling and conveying line in a cannig plant to apply a reflex-reflecting stripe on a can body prior to the passage of this can body to the filler and sealer, without requiring any major reworking, rearranging, or extra equipment in the assembly line.

The present invention provides a novel apparatus for handling cans to print a reflex-reflective stripe on the can body at substa-ntially any location along the length of said can body. The stripe may be continuous or intermittent.

The apparatus of the present invention provides a novel compact can-marking apparatus for applying a reflexreflective stripe to a can body in a two-step operation.

The present invention provides an apparatus with horizontally spaced applicating stations. The first station includes an applicating lroller rotating in a narrow reservoir through which the adhesive composition is circulated and in which several doctor blades are positioned to maintain the roller in good order. The second station applies the lens elements or reflex-reflective particles and includes an applicating roller which Idirectly applies the particles from a stream or fluidized bed of said particles to the tacky adhesive stripe on the can. The lluidized bed affords a continued supply of particles to the roller.

The present invention also permits placing the reflexreflective mark in the bead of the can (the depressed rings on cans for reinforcing) where they are protected. This was not practical with conventional markings.

A further advantage of the present invention is that the apparatus includes a novel combination of can spacing means, conveying means for lifting the cans, applying means for placing the stripe on the cans, means for returning the cans to a normal conveying line, and means for clearing the can marking apparatus should a jam or bottleneck develop in the assembly line beyond the marking machine.

The above and further advantages and features of the present invention will become more apparent after reading the following detailed description which refers to the accompanying drawing wherein:

FIGURE l is a generally schematic elevational view of a stripe applicator formed in accordance with the present invention;

v FIGURE 2 is an elevational view of the apparatus of FIGURE 1, with one side plate removed to show the interior and with some elements shown schematically; and

FIGURE 3 is a transverse sectional view taken along the line 3--3 of FIGURE 2.

Referring now to the accompanying drawing, there is shown in FIGURE 1 a schematic view of a marking apparatus, generally designated by the numeral 5, formed in accordance with the present invention and disposed between a supply conveyor 6 on the pallet unloader and a conveyor 7 leading to the filler in the assembly or processing line of a Cannery. The cans 8, to be marked, are received by the apparatus with the axis thereof disposed horizontally. The cans 8 enter the apparatus 5 by gravity down an inclined ramp. A feed and spacing wheel 9 moves the cans into the apparatus 5 as will hereinafter be explained.

Along conveyor 7 and spaced a distance, indicated by the bracket A, from the exit area or ramp of the apparatus 5 is a sensor 10 for sensing a stoppage of movement of the cans 8 past such sensor. The sensor 10 senses the stoppage and through suitable electrical switching means transmits a signal to stop further movement of cans 8 into the apparatus. The distance A to the sensor 10 from apparatus 5 is sufficient to receive all the cans that may be in the apparatus 5 at one time. Thus, if a bottleneck develops stopping cans and causing a jam beyond the apparat-us 5 the sensor stops further cans from entering the apparatus and allows the apparatus to clear at its normal pace. The result is that no cans are held in apparatus `5 while the jam is cleared which may cause a poor mark to be made on a can.

The sensor 10 may be any suitable can-operated mechanism and, as an example, may comprise a can-operable contact switch arm 11 and time delay relay such that its operation by each can does not signal a stoppage but the continued closure of the switch would send a signal to operate a barrier 13 (FIGURE 2) in the can entrance area to the apparatus 5.

The barrier 13 comprises a rotatable lever arm 14 having at its free end a projection which will, in the operated position, be placed into the path of the cans to stop the advance of the same toward the spacing wheel 9. Arm 14 may be rotated to an operative position by a shaft turned by a rotary solenoid 15 or other suitable mechanism, in response to receipt of the signal from sensor 10.

The apparatus 5 comprises a frame formed principally by vertically positioned transversely spaced side plates 21 and 22 supported by standards or legs 23 and 24. Each lof the plates 21 and 22 supports cantilever mounted guide rods 25 engageable with the end portions of the cylindrical can bodies 8 as they are moved through the apparatus. Also supported on the side plates 21 and 22 are transversely spaced, aligned guide rail members 26 and 27 dening a path along which the cans are moved through the machine. One guide member 27 is shown more clearly in FIGURE 2 and comprises a rigid frame member 28 attached to the plate 22, with the under surface thereof coated by a layer 29 of rubber-like material. The rail members 26 and 27 are formed with a central straight line stretch 31 and arcuate end sections 32 and 33, each arcuate end section being of an equal radius, with the end section 32 being joined to a tangential length 34 extending downward toward the feed and spacing wheel 9 of the apparatus. Directly beneath each of the rails and entrained around pulleys are a pair of driven V-belts 35 and 36 affording, together with the guide rails 26 and 27, a conveying means for the cans through the apparatus 5. The belts engage the cylindrical cans and roll them along the guide rails 26 and 27. Three sets of pulleys 37, 38 and 39 provide the principal path for the V-belts. Pulley sets 37 and 38 are mounted on shafts 41 and 42 which are concentric with the arcuate end portions 32 and 33 of the rails 26 and 27. The third pulley set 39 is positioned adjacent the leading end of the apparatus and is so located that the periphery of the belts will extend along a line parallel with the tangential length 34 of the rails 26 and 27. 4Positioned intermediate the pulleys 38 and 39 along the paths of the belts are active belt-tightening idler pulleys y44 mounted in the conventional manner with spring means -46 for placing tension in each V-belt, but permitting the belts to adjust to the position of the cans as they move along the straight stretch 31 of the rail members 26 and 27 `between the arcuate portions.

Adjustably positioned along the shaft 41 between the set of V-belt pulleys 37 is a coating assembly 51 for applying a band of adhesive material to a can 8, as it moves around the arcuate end 32 of the rails 26` and 27. This adhesive applicating or coating assembly 51 comprises a wheel 52 supported and driven by the shaft 41. The wheel 52 has a radius corresponding generally to the radius of the pulleys 37 and the added width of the V-belts extending about said pulleys. The applicating wheel 52 comprises a disk 53 on a hub, which hub is connected to the shaft for rotation therewith. The outer peripheral edge of the disk is covered with a band or tire 54 formed of a material which will carry the adhesive composition on its surface from a reservoir 56 into contacting relation with the surface of the can 8. A suitable material for such tire `54 is a silicone elastomer, which material will carry and allow transfer of the adhesive and provide some resilience upon contact with the can surface.

The wheel 52 runs in a supply of adhesive material and directly applies the material from the supply to the can surface as the can 8 is being driven rotatably about the arcuate ends 32 of the rail members 26 and 27. The reservoir or pot 56 for the adhesive material comprises a pair of side frame members 57 and 58, supported from the shaft 41 by attachment to bearing housings aligned with openings in the side frame members. The bearings prevent rotation of said side frame members and receive the trunnions of the disk hub through their centers and permit rotation of the shaft 41 and wheel 52. Plates 59, 61, and 62 which form the bottom and end walls of the reservoir respectively, extend transversely and are joined to side frame members 57 and 58. A keeper, xed to the bottom of plate 59, engages a fixed rod extending outwardly from plate 22 and prevents rotation of the pot 56. Joined to and communicating with the pot 56 adjacent either end of the bottom plate 59 are return conduits 63 and 64 permitting the return of adhesive material to a supply reservoir 60 such as a barrel or pail. The material is pumped by a suitable pump 65 (such as an airoperated piston or screw-type pump) mounted in the cover for the reservoir 60 to the pot 56 through a line 66 connected to plate 59 intermediate the return conduits.

As illustrated in FIGURE 2, the direction of rotation of the wheel 52 is counterclockwise, and a U-shaped doctor blade 67 is mounted adjustably adjacent the wheel 52 to control the amount of adhesive material carried on the periphery of the wheel and doctor the adjacenut end walls of the wheel before the surfaces leave the pot to apply the adhesive to the can body 8. The doctor blade 67 has the bight portion adjacent the disk periphery disposed normal to the projecting prongs which doctor the end walls, and a shaft is connected to the bight portion which is adjustable in the end wall. Positioned within the pot 56 and adjacent to the end walls of the applicating wheel are spring steel blades 68 which doctor the axially opposite end walls of the wheel as it rotates to restrict the amount of material carried by the end walls and the amount of material to be controlled by the doctor blade 67. The blades 68 are connected to the side frame members 57 and 58 and do not contact the end Iwalls of the wheel 52. A vertically positioned and transversely extending bar 71 is disposed between and joins the side plates 57 and 58 and the bottom plate 59 of the pot 56 to maintain an amount of adhesive material in the pot at least suicient to cover the periphery of the wheel. A doctor blade 72 made of polytetrafluoroethylene is provided adjacent the periphery of the wheel near plate 52 to contact and clean the outer peripheral surface of the tire 54. The blade 72 is supported from a bar extending transversely between frame members 57 and 58.

The coating assembly is adjustable between the pulleys 37 by sliding the shaft 41 axially in the pulleys. This is accomplished by releasing a set screw 73 in the drive sleeve 74 which is secured to and driven from one of the pulleys 37 as shown in FIGURE 3. This adjustment permits changes in the placement of the retro-reflective stripe axially along the can surface.

The use of the blades 68 within the pot to doctor the sides of the wheel were found to be necessary to prevent excess buildup of the adhesive on the wheel. The blades do not contact the end of the wheel however and thus prevent friction and heat which caused a loss of solvent in the adhesive composition and solidification, the result of which is a friction brake. Thus this novel repeated doctoring maintains an optimum amount of adhesive material on the outer cylindrical periphery of the wheel for application of a thin coat of adhesive to the can surface.

A second applicator 76 spaced from the coating assembly 51 applies a monolayer of reflex-reflective particles to the adhesive stripe on the can. Applicator 76 comprises a carrier wheel 77 having a hub and disk with a preferably resilient outer surface formed as a tire similar to the adhesive applicating wheel 52. A preferred material for the tire or outer peripheral surface of this wheel is a silicone elastomer or other similar material having a suitable releaseable surface attraction for small particles which permits the transport of a monolayer of the particles by the wheel. Wheel 77 is carried on and driven by the shaft 42 and is driven from one of the pulleys 38 similar to the drive for shaft 41. The shaft 42 is also axially adjustable to move applicator 76 to a position aligned with the adhesive applicator 51. The wheel 77 is rotated in a narrow chamber and the supply of reflex-reflecting particles is delivered to the carrier wheel 77 in a fluidized bed (the particles are maintained in continuous motion to prevent blockage and clogging of the same wthin the chamber or a supply reservoir).

The assembly for providing a supply of the reflex-reflecting particles to the carrier wheel 77 comprises a chamber formed by a pair of transversely spaced side plates 81 and 82 which are journalled on the hub of wheel 77 by bearings disposed on each side of said Wheel, similar to the plates 57 and 58 of applicator 51. The bottom 83 and end walls 84 and 186 complete the chamber for the particles and are formed to provide a trough permitting the elements to move a lower corner and return to a supply reservoir 87 through a hose 88. The particles in the reservoir 87 are vibrated by a vibrator 89 having a ring connected to the reservoir and operated by compressed air. Air is also forced up through the reservoir to keep the particles from blocking or packing. The particles are moved from the reservoir 87 to the chamber by means of an air jet 90 disposed in a line 91. In the chamber, the line 91 terminates in a tube 92 having a temrinal troughlike configuration adjacent the periphery of wheel 77. The particles are thus kept in motion through the system but a suicient quantity are contacting the wheel at all times to `be carried thereby into Contact with an adhesive stripe on a can as it is turned along the arcuate end portion 33 of the rail members. A deecting block 93 is disposed in the chamber beyond the end of the tube 92 to aid in maintaining a flow path of the particles so they contact the wheel 77 and the excess particles are returned to the supply reservoir 87. The compressed air for the vibrator 89, air jet 90, and for the air introduced into the bottom of the reservoir 87 is provided by a suitable source of compressed air such as a pressure pump 94.

The V-belts 35 and 36 and the applicating wheel 52 and carrier wheel 77 are driven from `a motor 96 by means of a sprocket 97, chain 98, and a sprocket 101 mounted on a shaft 102 carrying the set of belt pulleys 39. The can-feeding and spacing Wheel 9 moves the cans 8 into the marking apparatus and is driven from the shaft 102 by a chain 103 extending around a sprocket 104 on shaft 102, an idler sprocket 106, and a drive sprocket 107 on a shaft 108 supporting the Wheel 9. The spacing wheel 9 is a roller having a high-friction surface coating which engages the cylindrical surface of a can as it moves by gravity down an inclined ramp 109. The wheel 9 then drives the can into contact with the V-belts 35 and 36, which move it (together with the wheel 9) into contact with the tangential length 34 of the guide members 26 and 27. This rotatably driven wheel 9 prevents jamming and is considerably less damaging to the cans than the more conventional star wheels used in presently known can-conveying and printing equipment for spacing and moving cans. This wheel and belt system affords an automatic spacing for the cans and with the belts 3S and 36 moving at a linear velocity greater than the peripheral speed of the wheel 9 the spacing is obtained. This spacing is adjustable by adjustingthe speed of either the Wheel or belts and the desired spacing will be maintained throughout the apparatus.

If it is desired to print discontinuous retro-reflective or reex-reective stripes on the cans, the tire on one or the other of the rollers or wheels 52 and 77 may have an interrupted surface dened by axially extending circumferentially spaced slots formed therein. Such a structure is illustrated in the aforementioned copending application of Melvin L. Johnson.

The machine of the present invention is also adjustable to permit its use with cans of various lengths and suitable adjustments, as will be obvious to persons having ordinary skill in the art, can be made to utilize the present invention with cans or other cylindrical bodies of varying diameter.

Having thus disclosed the present invention, what is claimed is:

1. An apparatus for use in applying a coating of reflexreflecting material to the surface of a cylindrical body, said apparatus comprising a frame; stationary guide means on said frame affording a path for movement of a cylindrical body across said frame, said guide means including two horizontally spaced arcuate portions, the arcuate extent of which is at least equal to the circumference of a said body to be marked; movable belt means disposed beneath and in spaced relation to said guide means for contacting a said cylindrical body to press the body against the arcuate portions of said guide means to advance the body by rolling the same along said guide means; applicating wheels disposed adjacent each of said arcuate portions of said guide means with the axis of said wheels being disposed respectively -at the centers of said arcuate portions for imparting coatings to a said body as it moves therethrough, a first of saidapplicating wheels applying a stripe of adhesive material as the body moves along a first arcuate portion of said guide means, a second of said applicating wheels, aligned in the path of the body with said first wheel, for applying dry reilex-reflective material to said stripe of adhesive material as the body moves along the second arcuate portion of said guide means, said second wheel having a coating on its periphery having apreleasable attraction for said dry material; and means affording direct supply of said adhesive material; and means affording direct supply of said adhesive material and said dry material to the applicable applieating wheel.

2. The apparatus of claim 1 wherein said means affording direct supply of said adhesive material comprises a chamber disposed about the lower portion of said first Wheel, means supported within said chamber and spaced from each end wall of said first wheel for doctoring said ends, and means supported by said chamber for doctoring the adhesive material on the outer cylindrical peripheral surface of said irst wheel and the outer edges of said end Walls as said first wheel leaves said chamber.

3. The apparatus of claim 2 wherein said means affording direct supply of said adhesive material further comprises pump means for supplying adhesive from a reservoir to said chamber, a supply line connecting said pump means and said chamber, and a return line from said chamber to said reservoir to maintain circulation.

4. The apparatus of claim 1 wherein said means affording direct supply of said dry material to the second applieating wheel comprises means aifording ya continuous flow of said dry material into contact with the lower peripheral portion of said second wheel.

5. The apparatus of claim 1 wherein means are provided adjacent said first arcuate portion of said guide means for feeding said bodies into contact with said belt means and said guide means, said means for feeding including a driven roller positioned to engage successive cans, said roller having a smooth outer friction surface to engage the bodies and roll the same around an arcuate guide into contact with said belt means.

6. The apparatus of claim 1 wherein said guide means include similar rail members positioned in spaced planes, each member having a lower can-engaging surface and formed at each end with an arcuate portion the axis of which is normal to the plane of said rail member and having 'an intermediate portion joining said arcuate portions to dene a continuous guide through said apparatus.

7. An apparatus for placing a reex-reiiective mark on a can body by irst applying a stripe of an adhesive composition to the outer peripheral surface, partially drying the adhesive composition to a tacky state, and applying a layer of glass spheres on said adhesive composition while still in a tacky state, said apparatus comprising:

(A) frame means,

(B) can-conveying means supported by said frame means, said can-conveying means comprising (1) transversely spaced horizontally positioned rail members for engaging the cylindrical surface of said cans and defining a path along which said cans will move, said rail members having two horizontally spaced arcuate portions of equal radius,

(2) a pair of driven endless belts,

(3) pulley means for guiding said belts about a path below and spaced from siad rail members and including sets of pulleys each including a pair of transversely spaced pulleys mounted coaxially on a shaft, the axis of said shaft being positioned at the center of a said arcuate portion of said rail members, said belts and rail members cooperating to roll cans along said frame with the axis of said cans being horizontal,

(C) feed means for moving cans into engagement with said belts to be thereafter advanced along .said rail members, said feed means comprising (l) an arcuate ramp supporting said cans, and

.(2) -a driven roller having a friction surface engageable with said cans to advance them around said arcuate ramp into contact with said belts, the peripheral speed of the cancontacting surface of said roller being less than the lineal speed of said belts to space said cans during movement through said apparatus,

(D) means for coating adhesive on said can as it moves along a first of said arcuate portions of said rail members, said means for coating adhesive comprising (l) a narrow disk driven by a said shaft positioned at said first arcuate portion,

(2) container means positioned about the lower portion of said disk for supporting suicient adhesive to contact the periphery of said disk, and

(3) means for circulating said adhesive through said container means,

(E) applying means for contacting said adhesive coating on a can with glass spheres as said can moves through the second arcuate portion of said rail members, said applying means comprising (l) a second disk having a peripheral surface exhibiting a releasable attractive force for siad spheres, said disk being driven by a said shaft positioned at said second arcuate portion, and

(2) means for moving a stream of said spheres adjacent the periphery of said second disk, and

(F) drive means for said belts and said driven roller.

References Cited UNITED STATES PATENTS 935,229 9/1909 Phelps 118-219 XR 2,221,776 1l/l940 Carlson 156--241 2,425,236 8/1947 Ferrante 118-206 3,008,826 11/1961 Mott et al 96-1 WALTER A. SCHEEL, Primary Examiner.

R. I. SMITH, Assistant Examiner.

UNITED STATES PATENT GFFICE CERTIFICATE OF CORRECTION Patent No. 3,424,127 January 28, 1969 Melvin L. Johnson et al.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 70, "of" Should read for Column 6, line 65 Cancel "and means affording direct supply of said adhesive material; Column 8, line 33, siad" should read said Signed and sealed this 7th day of April 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr. E. JR.

Attesting Officer Commissioner of Patents 

